Plastic calibrating vacuum tank apparatus and tank therefor

ABSTRACT

A plastic calibrating vacuum tank and apparatus in which the tanks are formed at the top by a face positioned out of the horizontal plane and in which a cover is operable on a rear surface or face completing the tank top and in which the rear face is sloped and also out of the horizontal plane such that a cover hingedly connected thereto, when opened, will be limited in its projection beyond the rear of the tank.

United States Patent [1 1 [111 3,902,631

Gatto 51 Sept. 2, 1975 [54] PLASTIC CALIBRATING VACUUM TANK 999,374 8/1911 Kluge] 220/32 APPARATUS AND TANK THEREFOR 1,631,734 6/1927 Katzinger 220/23.2

2,565,448 8/1951 [76] Inventor: Charles Gatto, 45 Rabro Dr., 2 610 7 0 9 1952 Hauppauge, N.Y. 11787 2,726,004 12 1955 McLeod 220/4 1) [22] Filed: Feb. 8, 1974 Primary Examiner-W1l11am 1. Price PP NOJ 440,818 Assistant ExaminerJoseph lM. Moy

Attorney, Agent, or Firm-Bauer & Amer 52 U.S.C1 220/337;220/23.2;220/s5 R;

220/94 A; 220/335 57 ABSTRACT 51 Int. (:1. B65D 43/24; B65D 43/14 58 Field of Search 220/57, 24 R, 32,94 A, A Plastc Cahb'atmg vacuum tank and apparatus which the tanks are formed at the top by a face posi- 220/31 85 85 R tioned out of the horizontal plane and in which a cover is operable on a rear surface or face completing [56] References Cited the tank top and in which the rear face is sloped and UNITED STATES PATENTS also out of the horizontal plane such that a cover 363,664 5/1887 Metzger 220/31 R hingedly connected thereto, when opened, will be lim- 443,453 8/1391 McLaughlin-- 220/31 R ited in its projection beyond the rear of the tank. 523,125 7/l 894 Lebach '220/32 991,270 5/ 1911 Bunn 220/32 1 Claim, 3 Drawing Figures PLASTIC CALIBRATING VACUUM TANK APPARATUS AND TANK THEREFOR BACKGROUND OF THE INVENTION In the extrusion of plastic articles, it has been the practice to direct the extruded'product into a calibrator tank where the article is properly sized and cooled. Such calibrator tanks are also known as vacuum tanks filled at least partially with a liquid and in which a vac uum is applied.

More recently, it has become recognized that the productive output of the article forming plastic extruder could be enhanced if the same could supply the extruded product to more than one calibrator tank at the same time. Thus, by arranging the tanks in close back-to-back tandem relationship, the extruded products can be fed to two calibrator tanks simultaneously.

Unfortunately, the present structural arrangement of calibrator tank details does not easily allow for the convenient initial back-to-back tank arrangement within a reasonable area as to render the use of such dual tank apparatuses easy to use, efficient to operate or economical to utilize. One of the more limiting structural problems with such plastic calibrating vacuum tank apparatuses is the fact that access to the tank interior must be convenient and easily obtained without sacrificing the large access opening that is found to be necessary.

Another problem is the inability to arrange the tanks in such close back-to-back tandem relationship as to enable the economic use of small areas or spaces. This has not been possible because the need for large access openings to the tank interior dictates the use of relatively large access covers, which when opened rearward collide with each other with costly damaging results to the covers, the tanks and sometimes the people operating the same.

SUMMARY OF THE INVENTION The desideratum of this invention is to provide a' plastic calibrating vacuum tank apparatus and a tank structure therefor that will surmount and avoid all of the aforementioned problems.

Accordingly, an object and feature of the invention is to provide a calibrating vacuum tank having a novel arrangement of structural details at the top thereof that enables the provision of as large an access opening to the tank interior as may be needed and the operation ofa closure cover between a position to close the open ing and an open position whereat the same will be free of abutting or colliding engagement with a similar cover of a tank in close back-to-back relationship therewith.

The above description, as well as further objects. features and advantages of the present invention, will be more fully appreciated by reference to the following detailed description of a presently preferred. but nonetheless illustrative. embodiment in accordance with the present invention, when taken in conjunction with the accompanying drawings, wherein:

DESCRIPTION OF THE DRAWINGS FIG. I is a perspective view of a portion ofa calibrating vacuum tank constructed according to the teaching of the invention;

FIG. 2 is an end view of a calibrating vacuum tank apparatus with one of the tanks shown in cross-section taken along the lines 22 of FIG. 1; and

FIG. 3 is a perspective view of a cover hinge.

Referring now to the drawing, the numeral 10 generally identifies a plastic calibrating vacuum tank apparatus as shown in FIG. 1 with the tanks thereof generally identified by the numeral 12. The pertinent details of the tanks 12 are more fully illustrated in FIG. 1. In the apparatus 10, the pair of tanks 12 are arranged backto-back to extend lengthwise in tandem relationship and in substantial alignment with a plastic extruder that is not shown and forms no part of the present invention.

As is common, the tanks 12 are generally elongated in length. Each tank 12 has a bottom 14, a rear wall 16, a front wall 18 and opposite end walls 20 (only one of which is shown in the Figures of the drawing). The walls so described are air-tightly interconnected with each other and with a top that generally forms the closure of the tank. In prior art tanks to which the present invention relates, it has been the practice to arrange the tank top along a horizontal plane with an opening defined therein such that access to the tank interior was afforded by reaching over the front wall and downward into the tank interior. To facilitate access to the tank interior and to close the access opening when necessary to apply a vacuum thereto, a cover was hinged to the rear wall to pivot between open and closed positions. When so arranged, the cover was retained in its open position by tilting it rearward beyond a vertical plane and beyond the rear walls so that it would not fall forward and close of its own weight.

Unfortunately, such arrangement of tank structure was satisfactory when a single tank was used in line with a single plastic extruder. With the advent of tandem or back-to-back tank apparatuses, it became clear that the tank structures and their arrangements of details limited the tandem spacing between tank backs. As a result of the prior tank structures, it was necessary to allow for the rearward pivotal movements of the covers such that they would not hit or collide with each other to cause damage when two covers. in back-toback relationship, were opened at the same time. Thus,

spacing requirements between back-to-back tanks became an important problem and an impediment to the positioning of such tanks in tandem relationship in the extrusion system or line.

In the present invention, the tank 12 is provided with a multi-piece or plural element top in which the same is formed by the fluid-tight interconnecting or jointure of rear and forward or front faces or surfaces 22 and 24 respectively along a line 25. In this arrangement, the rear face 22 is fluid-tightly connected with the rear wall 16 while the front surface or face 24 is fluid-tightly joined with the front wall 18. As has been the practice, each tank 12 is provided with an inlet 26 at the end wall facing the extruder for the introduction and continuous movement of extruded products thereinto. A similar outlet opening (not shown) is provided in the opposite end wall for the exiting movement of the extruded product from the tank 12.

Unlike prior art tanks, the parts 22 and 24 of the top of the tank 12 are directed upward out of the horizontal plane of the tank. To this end, the front surface 24 is joined with the front wall I8 along a horizontal line 26 that is lower than the line of jointure 28 between the rear surface 22 and the rear wall 16. The interconnection 25 between the top surfaces 22 and 24 is located along a line or position that is intermediate the rear and front walls 16 and 18, but located more toward the rear wall 16. This enables the front surface 24 to slope at an angle to the horizontal that is less than that of the rear face 22. As a consequence, the rearward extent of the surface 24 is greater than is the forward extent of the surface 22. Hence, the surface 24 presents a flatter angle to the horizontal than does the rear face 22 but also presents a greater portion of its extent to the front wall of the tank for a purpose that will become apparent as the description proceeds.

Defined within the front surface 24 is an access opening 30 that is outlined by the defining margin of the surface 24. Because the surface 24 is angled upward and rearward, much of the access opening 30 is visible at the front of the tank 12 and, therefore, access to the interior is more readily enabled.

Mounted for manual opening and closing movement relative to the access opening 30 is a curved cover 32 that extends along and for covering the full length of the opening 30. The cover 32 is formed with a flat marginal seat 34 on which a sealing gasket 36 is secured for fluid-tight flat sealing engagement with and about the marginal flat surface 24. The cover 32 is manually manipulated between open and closed positions by handles 38 that may be relatively spaced from each other along the length of the cover.

The pivotal movement of the cover 32 is enabled by hinge means that are secured to the top of the tank. An enlarged detail of a preferred hinge structure is illustrated in FIG. 3 wherein a housing 40 may be secured to the rear surface 22 of the tank top at cars 42 by any convenient securing means as bolts, screws or the like, not shown. The housing 40 has a slot 44 in which a block 46 slides. The block 46 is bifurcated with wings 48 through which a hinge or pivot pin 50 extends.

The handles 38 each are secured to the cover 32 in any convenient manner, not shown, and terminate at their forward ends in a manipulatable knob 52 and at their opposite ends they are pivotally connected to the tank top by the hinge 50. A projection or stop 54 is adapted to engage with either the housing 40 or with the rear surface 22 to limit the rearward pivoting movement of the cover 32. By mounting the hinge on the rear surface 22 and locating the pivot 50 in a line intermediate the rear and front walls 16 and 18, when the cover 32 is moved to its open broken line position as shown in FIG. 2, it will pivot at a location forward of the plane of the rear wall 16. The angle of rearward tilt of the cover may be predeterminately limited by the length of the projection 54 which may be adjustable if desired.

All that is required to retain the cover 32 in its open position is a sufficient angle of rearward tilt such that the cover will not fall forward of its own weight or by slight accidental forward force applied to it. For this reason, it is important to enable the cover to tilt rearward in its open position an amount sufficient to cause it to remain open until manually closed. Thus, by arranging the top of the tank with its surfaces 22 and 24 as disclosed and mounting the cover hinge point 50 on the top at a location remote from the rear wall 16,

when the cover is opened fully, no part of the same will extend or project beyond the rear wall or a plane extending upward therefrom.

When a pair of tanks 12 are arranged in tandem back-to-back relationship as shown in FIG. 2, it is desirable that the space between them be as small as possible. This possibility is capable of being accomplished by the present invention since the opened covers 32 will not project beyond the vertical planes of their respective rear walls. Hence, the relative spacing between the tanks can be as small as desired. However, in those instances where the back-to-back spacing between tanks 12 is able to be increased, the covers 32 may be permitted a greater angle of rearward tilt. In such instances, the stop projections 54 may be adjusted to permit the covers to tilt to an extent such that the cover will extend up to but short of the center line 56 of the space between the tanks 12.

While there have been shown and described and pointed out the fundamental novel features of the invention as applied to a preferred embodiment thereof, it will be understood that various omissions and substitutions and changes in the form and details of the device illustrated and in its operation may be made by those skilled in the art without departing from the spirit of the invention. It is the intention, therefore, to be limited only as indicated by the scope of the claims appended hereto What is claimed is:

l. In an apparatus for calibrating plastic articles wherein,

a plurality of longitudinally extending vacuum tanks are positioned in back-to-back spaced relationship, and in which said tanks each has an access opening and an operable cover to open and close said access opening, a front, a front face, a rear, and a rear face the invention comprising each tank having at the top thereof said front face at an angle to and sloping upward from the horizontal and directed upward and rearward from the front and a rear face at an angle to and sloping upward from the horizontal and directed upward and forward from the back of the tank for fluid-tight connection with said front face to complete the tank top,

the rearward extent of said front face being greater than the forward extent of said rear face and the fluid-tight connection therebetween defining the top closure of the tank,

said access opening being defined in said front face and the upward angle of said front face and access opening being less than that of said rear face,

and cover hinge means mounted on said rear face and connected with and to enable the operation of said cover between a position to close said access opening and a position to limit the opening movement of the cover upward and rearward short of a plane extending upward from between the center of the space between the backs of the spaced tanks.

k l =l I 

1. In an apparatus for calibrating plastic articles wherein, a plurality of longitudinally extending vacuum tanks are positioned in back-to-back spaced relationship, and in which said tanks each has an access opening and an operable cover to open and close said access opening, a front, a front face, a rear, and a rear face the invention comprising each tank having at the top thereof said front face at an angle to and sloping upward from the horizontal and directed upward and rearward from the front and a rear face at an angle to and sloping upward from the horizontal and directed upward and forward from the back of the tank for fluid-tight connection with said front face to complete the tank top, the rearward extent of said front face being greater than the forward extent of said rear face and the fluid-tight connection therebetween defining the top closure of the tank, said access opening being defined in said front face and the upward angle of said front face and access opening being less than that of said rear face, and cover hinge means mounted on said rear face and connected with and to enable the operation of said cover between a position to close said access opening and a position to limit the opening movement of the cover upward and rearward short of a plane extending upward from between the center of the space between the backs of the spaced tanks. 